Fuses are among the most important electrical components in the world. Without fuses, it would be virtually impossible to run any type of electrical circuit safely, save for the smallest circuits that consume the lowest amounts of current.
A fuse is actually a resistor. A fuse is also a device that, when functioning properly, is actually destroyed if conditions that require it to perform its function should come about. A fuse is a device designed to provide a way of protecting against an overcurrent condition in a circuit.
Fuses come in many shapes and sizes, but there are some designs that will be very familiar to people. One is the classic design that looks like a glass capsule with two metal ends. Those ends provide the contact points for the fuse. Within the metal capsule is a filament, usually made out of metal.
Fuses have current and voltage ratings that are very important to selecting them. These current and voltage ratings are commonly found imprinted on the fuse. Additional information, such as a time-current characteristic, breaking capacity and information specific to the component itself – such as the part number – are oftentimes imprinted on the fuse, as well.
Because the fuse is a consumable electronic component, it will be manufactured in a way that is standardized. This allows a burnt out fuse to be quickly and easily replaced.
In household applications, fuse boxes have largely been replaced by circuit breaker boxes. These are more convenient and, in many regards, safer for consumers to use. In electronics applications, however, a fuse box sometimes provides the ideal solution for providing safety for circuits. They are very compact and, where the parts are concerned, fuses are very inexpensive and easily replaced. Fuses, in fact, are generally bought in very large quantities with different amperage ratings included in the purchase.